反应详情

A mixture comprising the rac-tert-butyl 7,8-dihydroxy-2,3-diphenyl-7,8-dihydropyrido[2,3-b]pyrazine-5(6H)-carboxylate (step 2) (230 mg, 0.548 mmol), acetic anhydride (155 μl, 1.645 mmol) and pyridine (1064 μl, 13.16 mmol) was stirred at RT under an atmosphere of nitrogen overnight. After standing at RT for 2 days, the mixture was diluted with saturated sodium bicarbonate and extracted with DCM (2×20 ml). The organic extracts were combined and concentrated in vacuo. The crude material was purified by chromatography on silica eluting with 20-100% EtOAc/iso-hexane to afford the title compound;

1. waitAfter standing at RT for 2 days
2. extractionextracted with DCM (2×20 ml)
3. concentrationconcentrated in vacuo
4. customThe crude material was purified by chromatography on silica eluting with 20-100% EtOAc/iso-hexane